feat(nodejs): add create static method

README.md

@@ -55,8 +55,8 @@ example result:
 
 node:
 ```
-> const IP2Region = require('./ip2region.js');
+> let ip2region = require('./ip2region.js');
-> const dbService = new IP2Region({dbPath: './ip2region.db'});
+> let dbService = ip2region.create('./ip2region.db');
 > dbService.binarySearchSync(' 101.105.35.57')
 { city: 0, region: '中国|0|广东|深圳|鹏博士' }
 ```

binding/nodejs/ip2region.js

@@ -54,6 +54,10 @@ function getLong(buffer, offset) {
  */
 
 class IP2Region {
+    static create(dbPath) {
+        return new IP2Region({dbPath});
+    }
+
     constructor(options = {}) {
         const { dbPath } = options;
         if (!dbPath || !fs.existsSync(dbPath)) {

binding/nodejs/ip2region.spec.js

@@ -5,7 +5,7 @@ describe('ip2region', () => {
   let instance;
 
   beforeAll(() => {
-    instance = new IP2Region({dbPath: path.join(__dirname, '../../data/ip2region.db')});
+    instance = IP2Region.create(path.join(__dirname, '../../data/ip2region.db'));
   });
 
   afterAll(() => {